Shape changing ablation balloon

Abstract

A device, method, and system for thermally affecting tissue. The device may generally include an elongate body, an actuation element slidably disposed within the elongate body, a balloon defining an interior chamber, a proximal neck, and a distal neck, the first neck being coupled to the distal portion of the elongate body and the second neck being coupled to the distal portion of the actuation element, retraction of the actuation element within the elongate body causing the treatment element to transition from a first configuration to a second configuration. The distal neck may be located external to the interior chamber in the first configuration and within the interior chamber in the second configuration. The device may also include a fluid injection element that is transitionable to an expanded configuration when the balloon is inflated, thereby enhancing the cooling capacity of the balloon.

What is claimed is: 
     
       1. A medical device for thermally affecting tissue, the medical device comprising:
 an elongate body including a distal portion and a proximal portion; 
 an actuation element slidably disposed within the elongate body, the actuation element including a distal portion and a proximal portion; 
 an inflatable treatment element defining an interior chamber, a first neck, and a second neck, the first neck being coupled to the distal portion of the elongate body and the second neck being coupled to the distal portion of the actuation element; and 
 
       a fluid injection element located within the interior chamber of the treatment element, the fluid injection element having a first configuration in which the fluid injection element is substantially in contact with the actuation element and a second configuration in which at least a portion of the fluid injection element is expanded away from the actuation element,
 retraction of the actuation element within the elongate body causing the treatment element to transition from a first configuration to a second configuration, each of the first and second necks being located external to the interior chamber in the first configuration and the second neck being located within the interior chamber in the second configuration, the fluid injection element being in the first configuration when the treatment element is in the first configuration and the fluid injection element being in the second configuration when the treatment element is in the second configuration. 
 
     
     
       2. The medical device of  claim 1 , wherein the treatment element is a cryoballoon. 
     
     
       3. The medical device of  claim 1 , wherein the second neck of the treatment element includes a first portion and a second portion, the first portion being coupled to the actuation element. 
     
     
       4. The medical device of  claim 3 , wherein the second portion of the second neck is not directly coupled to the actuation element. 
     
     
       5. The medical device of  claim 3 , wherein the first portion of the second neck is bonded to the actuation element. 
     
     
       6. The medical device of  claim 3 , wherein the first portion of the second neck is mechanically coupled to the actuation element. 
     
     
       7. The medical device of  claim 3 , wherein the second portion of the second neck separates from the actuation element when the treatment element is in the second configuration. 
     
     
       8. The medical device of  claim 7 , wherein the first and second portions of the second neck each have an inner surface and an outer surface, the outer surface of the second portion of the second neck being in contact with the outer surface of the first portion of the second neck when the treatment element is in the second configuration. 
     
     
       9. The medical device of  claim 1 , wherein the distal portion of the actuation element includes a distal tip, the second neck being coupled to the actuation element proximate the distal tip. 
     
     
       10. The medical device of  claim 1 , wherein the treatment element defines a distal face when the treatment element is in the second configuration. 
     
     
       11. The medical device of  claim 10 , wherein the treatment element defines a maximum outer diameter when in the second configuration. 
     
     
       12. The medical device of  claim 11 , wherein the maximum outer diameter is located a distance proximal from the distal face. 
     
     
       13. The medical device of  claim 12 , wherein the distance is between approximately 3 mm and approximately 6 mm. 
     
     
       14. The medical device of  claim 11 , wherein the maximum outer diameter is located immediately proximal to the distal face. 
     
     
       15. The medical device of  claim 11 , wherein a distance between the maximum outer diameter and the distal face changes as the treatment element transitions between the first configuration and the second configuration. 
     
     
       16. The medical device of  claim 1 , wherein the fluid injection element has a plurality of ports, at least some of the plurality of ports being proximate an inner wall of the treatment element when the treatment element is in the second configuration.